class Person {

	constructor(name: string) {
		this.name = name;
	}

	public name: string | undefined = undefined;
}

interface Test {

	add(a: number, b: number): number;
}
interface Test1 {

}
class Student extends Person implements Test, Test1 {

	add(a: number, b: number): number {
		console.log(this.name);
		return a + b;
	}



}

let st = new Student("fyuc");
st.add(1, 2);

let ts1: Test = new Student("dfjkhjksdhf");
ts1.add(1, 20);